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                    updateSuspenseComponent
            
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                    updatePortalComponent
            
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                    updateForwardRef
            
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                    updateFragment
            
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                    updateMode
            
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                    updateProfiler
            
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                    updateContextProvider
            
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                    挂起任务的含义
            
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                    lazy 组件
            
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                                <div class="api-method"><div class="api-method-definition"><h1 id="useeffect">useEffect</h1><p><code>effect</code>&#x4E5F;&#x5C31;&#x662F;&#x5728;React&#x4E2D;&#x6211;&#x4EEC;&#x5E38;&#x8BF4;&#x7684;<code>side effect</code>&#xFF0C;&#x5728;React&#x4E2D;&#x7C7B;&#x4F3C;&#x50CF;<code>componentDidMount</code>&#x8FD9;&#x6837;&#x7684;&#x751F;&#x547D;&#x5468;&#x671F;&#x65B9;&#x6CD5;&#x4E2D;&#xFF0C;&#x56E0;&#x4E3A;&#x53EF;&#x80FD;&#x4F1A;&#x6267;&#x884C;<code>setState</code>&#x8FD9;&#x6837;&#x7684;&#x65B9;&#x6CD5;&#x800C;&#x4EA7;&#x751F;&#x65B0;&#x7684;&#x66F4;&#x65B0;&#xFF0C;&#x6211;&#x4EEC;&#x79F0;&#x4E4B;&#x4E3A;<code>side effect</code>&#x5373;&#x526F;&#x4F5C;&#x7528;&#x3002;&#x672C;&#x8EAB;<code>FunctionalComponent</code>&#x56E0;&#x4E3A;&#x662F;<code>pure function</code>&#xFF0C;&#x6240;&#x4EE5;&#x4E0D;&#x4F1A;&#x4EA7;&#x751F;&#x4EFB;&#x4F55;&#x7684;&#x526F;&#x4F5C;&#x7528;&#xFF0C;&#x800C;<code>useEffect</code>&#x548C;<code>useLayoutEffect</code>&#x5219;&#x662F;&#x5E26;&#x7ED9;<code>FunctionalComponent</code>&#x4EA7;&#x751F;&#x526F;&#x4F5C;&#x7528;&#x80FD;&#x529B;&#x7684;Hooks&#xFF0C;&#x4ED6;&#x4EEC;&#x7684;&#x884C;&#x4E3A;&#x975E;&#x5E38;&#x7C7B;&#x4F3C;<code>componentDidMount</code>&#x548C;<code>componentDidUpdate</code></p><p>&#x4ED6;&#x4EEC;&#x63A5;&#x53D7;&#x4E00;&#x4E2A;&#x65B9;&#x6CD5;&#x4F5C;&#x4E3A;&#x53C2;&#x6570;&#xFF0C;&#x8BE5;&#x65B9;&#x6CD5;&#x4F1A;&#x5728;&#x6BCF;&#x6B21;&#x6E32;&#x67D3;&#x5B8C;&#x6210;&#x4E4B;&#x540E;&#x88AB;&#x8C03;&#x7528;&#xFF1B;&#x5176;&#x6B21;&#x8FD8;&#x63A5;&#x53D7;&#x7B2C;&#x4E8C;&#x4E2A;&#x53C2;&#x6570;&#xFF0C;&#x662F;&#x4E00;&#x4E2A;&#x6570;&#x7EC4;&#xFF0C;&#x8FD9;&#x4E2A;&#x6570;&#x7EC4;&#x91CC;&#x7684;&#x6BCF;&#x4E00;&#x4E2A;&#x5185;&#x5BB9;&#x90FD;&#x4F1A;&#x88AB;&#x7528;&#x6765;&#x8FDB;&#x884C;&#x6E32;&#x67D3;&#x524D;&#x540E;&#x7684;&#x5BF9;&#x6BD4;&#xFF0C;&#x5982;&#x679C;&#x6CA1;&#x6709;&#x53D8;&#x5316;&#xFF0C;&#x5219;&#x4E0D;&#x4F1A;&#x8C03;&#x7528;&#x8BE5;&#x526F;&#x4F5C;&#x7528;&#x3002;</p><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">createFunctionComponentUpdateQueue</span>(<span class="hljs-params"></span>): <span class="hljs-title">FunctionComponentUpdateQueue</span> </span>{
  <span class="hljs-keyword">return</span> {
    lastEffect: <span class="hljs-literal">null</span>,
  };
}

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">pushEffect</span>(<span class="hljs-params">tag, create, destroy, inputs</span>) </span>{
  <span class="hljs-keyword">const</span> effect: Effect = {
    tag,
    create,
    destroy,
    inputs,
    <span class="hljs-comment">// Circular</span>
    next: (<span class="hljs-literal">null</span>: any),
  };
  <span class="hljs-keyword">if</span> (componentUpdateQueue === <span class="hljs-literal">null</span>) {
    componentUpdateQueue = createFunctionComponentUpdateQueue();
    componentUpdateQueue.lastEffect = effect.next = effect;
  } <span class="hljs-keyword">else</span> {
    <span class="hljs-keyword">const</span> lastEffect = componentUpdateQueue.lastEffect;
    <span class="hljs-keyword">if</span> (lastEffect === <span class="hljs-literal">null</span>) {
      componentUpdateQueue.lastEffect = effect.next = effect;
    } <span class="hljs-keyword">else</span> {
      <span class="hljs-keyword">const</span> firstEffect = lastEffect.next;
      lastEffect.next = effect;
      effect.next = firstEffect;
      componentUpdateQueue.lastEffect = effect;
    }
  }
  <span class="hljs-keyword">return</span> effect;
}</code></pre>
<p>&#x4E0D;&#x96BE;&#x53D1;&#x73B0;&#x8FD9;&#x4E2A;&#x8FC7;&#x7A0B;&#x5176;&#x5B9E;&#x5C31;&#x662F;&#x5F80;&#x5F53;&#x524D;<code>Fiber</code>&#x4E0A;&#x589E;&#x52A0;&#x4E00;&#x7CFB;&#x5217;<code>effectTag</code>&#xFF0C;&#x5E76;&#x4E14;&#x4F1A;&#x521B;&#x5EFA;<code>updateQueue</code>&#xFF0C;&#x8FD9;&#x8DDF;<code>HostComponent</code>&#x7C7B;&#x4F3C;&#xFF0C;&#x8FD9;&#x4E2A;<code>queue</code>&#x4F1A;&#x5728;<code>commit</code>&#x9636;&#x6BB5;&#x88AB;&#x6267;&#x884C;&#x3002;&#x8FD9;&#x91CC;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x6CE8;&#x610F;&#x7684;&#x662F;<code>useLayoutEffect</code>&#x548C;<code>useEffect</code>&#x589E;&#x52A0;&#x7684;<code>effectTag</code>&#x662F;&#x4E0D;&#x4E00;&#x6837;&#x7684;&#xFF0C;&#x6240;&#x4EE5;&#x4ED6;&#x4EEC;&#x6267;&#x884C;&#x7684;&#x65F6;&#x673A;&#x4E5F;&#x662F;&#x4E0D;&#x4E00;&#x6837;&#x7684;&#x3002;<code>effectTag</code>&#x4F1A;&#x6709;&#x4EE5;&#x4E0B;&#x51E0;&#x79CD;&#x60C5;&#x51B5;&#xFF1A;</p><ul><li><code>useLayoutEffect</code>&#x589E;&#x52A0;<code>UpdateEffect</code>
</li>
<li><code>useEffect</code>&#x589E;&#x52A0;<code>UpdateEffect | PassiveEffect</code>
</li></ul>
<p>&#x4EE5;&#x4E0A;&#x662F;&#x589E;&#x52A0;&#x5728;<code>Fiber</code>&#x5BF9;&#x8C61;&#x4E0A;&#x7684;&#xFF0C;&#x800C;&#x8BB0;&#x5F55;&#x5BF9;&#x5E94;Hook&#x5BF9;&#x8C61;&#x7684;<code>effectTag</code>&#x5982;&#x4E0B;&#xFF1A;</p><ul><li><code>useLayoutEffect</code>&#x589E;&#x52A0;<code>UnmountMutation | MountLayout</code>
</li>
<li><code>useEffect</code>&#x589E;&#x52A0;<code>UnmountPassive | MountPassive</code>
</li>
<li>&#x5982;&#x679C;<code>areHookInputsEqual</code>&#x7B26;&#x5408;&#xFF0C;&#x5219;&#x589E;&#x52A0;<code>NoHookEffect</code>
</li></ul>
<p>&#x8BB0;&#x4F4F;&#x8FD9;&#x4E9B;&#x5185;&#x5BB9;&#xFF0C;&#x6211;&#x4EEC;&#x53BB;&#x770B;<code>commit</code>&#x9636;&#x6BB5;&#x505A;&#x4E86;&#x4EC0;&#x4E48;&#x8DDF;Hook&#x6709;&#x5173;&#x7684;&#x5185;&#x5BB9;</p></div><div class="api-method-code"><div class="api-method-sample" data-lang="js" data-name="JavaScript"><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">useLayoutEffect</span>(<span class="hljs-params">
  create: (</span>) =&gt; <span class="hljs-title">mixed</span>,
  <span class="hljs-title">inputs</span>: <span class="hljs-title">Array</span>&lt;<span class="hljs-title">mixed</span>&gt; | <span class="hljs-title">void</span> | <span class="hljs-title">null</span>,
): <span class="hljs-title">void</span> </span>{
  useEffectImpl(UpdateEffect, UnmountMutation | MountLayout, create, inputs);
}

<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">useEffect</span>(<span class="hljs-params">
  create: (</span>) =&gt; <span class="hljs-title">mixed</span>,
  <span class="hljs-title">inputs</span>: <span class="hljs-title">Array</span>&lt;<span class="hljs-title">mixed</span>&gt; | <span class="hljs-title">void</span> | <span class="hljs-title">null</span>,
): <span class="hljs-title">void</span> </span>{
  useEffectImpl(
    UpdateEffect | PassiveEffect,
    UnmountPassive | MountPassive,
    create,
    inputs,
  );
}

<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">useEffectImpl</span>(<span class="hljs-params">fiberEffectTag, hookEffectTag, create, inputs</span>): <span class="hljs-title">void</span> </span>{
  currentlyRenderingFiber = resolveCurrentlyRenderingFiber();
  workInProgressHook = createWorkInProgressHook();

  <span class="hljs-keyword">let</span> nextInputs = inputs !== <span class="hljs-literal">undefined</span> &amp;&amp; inputs !== <span class="hljs-literal">null</span> ? inputs : [create];
  <span class="hljs-keyword">let</span> destroy = <span class="hljs-literal">null</span>;
  <span class="hljs-keyword">if</span> (currentHook !== <span class="hljs-literal">null</span>) {
    <span class="hljs-keyword">const</span> prevEffect = currentHook.memoizedState;
    destroy = prevEffect.destroy;
    <span class="hljs-keyword">if</span> (areHookInputsEqual(nextInputs, prevEffect.inputs)) {
      pushEffect(NoHookEffect, create, destroy, nextInputs);
      <span class="hljs-keyword">return</span>;
    }
  }

  currentlyRenderingFiber.effectTag |= fiberEffectTag;
  workInProgressHook.memoizedState = pushEffect(
    hookEffectTag,
    create,
    destroy,
    nextInputs,
  );
}</code></pre>
</div></div></div>



<hr><div class="api-method"><div class="api-method-definition"><h1 id="commit&#x9636;&#x6BB5;hook&#x76F8;&#x5173;&#x7684;&#x5185;&#x5BB9;">commit&#x9636;&#x6BB5;Hook&#x76F8;&#x5173;&#x7684;&#x5185;&#x5BB9;</h1><p>&#x5728;&#x4EE5;&#x4E0B;&#x4E09;&#x4E2A;&#x9636;&#x6BB5;&#x90FD;&#x4F1A;&#x8C03;&#x7528;<code>commitHookEffectList</code>&#x65B9;&#x6CD5;&#xFF0C;&#x6211;&#x4EEC;&#x6765;&#x770B;&#x4E00;&#x4E0B;&#xFF1A;</p><ul><li><code>commitWork</code>&#x4E2D;<code>commitHookEffectList(UnmountMutation, MountMutation, finishedWork);</code>
</li>
<li><code>commitBeforeMutationLifeCycles</code>&#x4E2D;<code>commitHookEffectList(UnmountSnapshot, NoHookEffect, finishedWork);</code>
</li>
<li><code>commitLifeCycles</code>&#x4E2D;<code>commitHookEffectList(UnmountLayout, MountLayout, finishedWork);</code>
</li></ul>
<p><code>commitHookEffectList</code>&#x8FD9;&#x4E2A;&#x65B9;&#x6CD5;&#x7684;&#x5185;&#x5BB9;&#x5C31;&#x662F;&#x6839;&#x636E;&#x4F20;&#x5165;&#x7684;<code>unmountTag</code>&#x548C;<code>mountTag</code>&#x6765;&#x5224;&#x65AD;&#x662F;&#x5426;&#x9700;&#x8981;&#x6267;&#x884C;&#x5BF9;&#x5E94;&#x7684;<code>destory</code>&#x548C;<code>create</code>&#x65B9;&#x6CD5;&#xFF0C;&#x8FD9;&#x662F;&#x5728;&#x6BCF;&#x4E2A;<code>Hook</code>&#x5BF9;&#x8C61;&#x7684;<code>effect</code>&#x94FE;&#x4E0A;&#x7684;&#x3002;&#x6240;&#x4EE5;&#x770B;&#x8FD9;&#x90E8;&#x5206;&#x4EE3;&#x7801;&#x6700;&#x91CD;&#x8981;&#x7684;&#x5176;&#x5B9E;&#x5C31;&#x662F;&#x770B;&#x4ED6;&#x4F20;&#x5165;&#x7684;<code>effectTag</code>&#x548C;Hook&#x5BF9;&#x8C61;&#x4E0A;&#x7684;<code>effectTag</code>&#x7684;&#x5BF9;&#x6BD4;&#x3002;</p><p>&#x5BF9;&#x6BD4;&#x7ED3;&#x679C;&#x5C31;&#x662F;&#xFF1A;</p><ol><li><code>useLayoutEffect</code>&#x7684;<code>destory</code>&#x4F1A;&#x5728;<code>commitWork</code>&#x7684;&#x65F6;&#x5019;&#x88AB;&#x6267;&#x884C;&#xFF1B;&#x800C;&#x4ED6;&#x7684;<code>create</code>&#x4F1A;&#x5728;<code>commitLifeCycles</code>&#x7684;&#x65F6;&#x5019;&#x88AB;&#x6267;&#x884C;&#x3002;
</li>
<li><code>useEffect</code>&#x5728;&#x8FD9;&#x4E2A;&#x6D41;&#x7A0B;&#x4E2D;&#x90FD;&#x4E0D;&#x4F1A;&#x88AB;&#x6267;&#x884C;&#x3002;
</li></ol>
<p>&#x53EF;&#x4EE5;&#x770B;&#x51FA;&#x6765;<code>useLayoutEffect</code>&#x7684;&#x6267;&#x884C;&#x8FC7;&#x7A0B;&#x8DDF;<code>componentDidMount</code>&#x548C;<code>componentDidUpdate</code>&#x975E;&#x5E38;&#x76F8;&#x4F3C;&#xFF0C;&#x6240;&#x4EE5;React&#x5B98;&#x65B9;&#x4E5F;&#x8BF4;&#x4E86;&#xFF0C;&#x5982;&#x679C;&#x4F60;&#x4E00;&#x5B9A;&#x8981;&#x9009;&#x62E9;&#x4E00;&#x4E2A;&#x7C7B;&#x4F3C;&#x4E8E;&#x751F;&#x547D;&#x5468;&#x671F;&#x65B9;&#x6CD5;&#x7684;Hook&#xFF0C;&#x90A3;&#x4E48;<code>useLayoutEffect</code>&#x662F;&#x4E0D;&#x4F1A;&#x9519;&#x7684;&#x90A3;&#x4E2A;&#xFF0C;&#x4F46;&#x662F;&#x6211;&#x4EEC;&#x63A8;&#x8350;&#x4F60;&#x4F7F;&#x7528;<code>useEffect</code>&#xFF0C;&#x5728;&#x4F60;&#x6E05;&#x9664;&#x4ED6;&#x4EEC;&#x7684;&#x533A;&#x522B;&#x7684;&#x524D;&#x63D0;&#x4E0B;&#xFF0C;&#x540E;&#x8005;&#x662F;&#x66F4;&#x597D;&#x7684;&#x9009;&#x62E9;&#x3002;</p><p>&#x90A3;&#x4E48;<code>useEffect</code>&#x4EC0;&#x4E48;&#x65F6;&#x5019;&#x88AB;&#x8C03;&#x7528;&#x5462;&#xFF1F;</p><p>&#x7B54;&#x6848;&#x5728;<code>commitRoot</code>&#x7684;&#x6700;&#x540E;&#xFF0C;&#x4ED6;&#x7B49;&#x5176;&#x4ED6;<code>sideEffect</code>&#x5168;&#x90E8;<code>commit</code>&#x5B8C;&#x4E86;&#x4E4B;&#x540E;&#xFF0C;&#x4F1A;&#x6267;&#x884C;&#x4EE5;&#x4E0B;&#x4EE3;&#x7801;&#xFF1A;</p><pre><code class="lang-js"><span class="hljs-keyword">if</span> (
  enableHooks &amp;&amp;
  firstEffect !== <span class="hljs-literal">null</span> &amp;&amp;
  rootWithPendingPassiveEffects !== <span class="hljs-literal">null</span>
) {
  <span class="hljs-keyword">let</span> callback = commitPassiveEffects.bind(<span class="hljs-literal">null</span>, root, firstEffect);
  passiveEffectCallbackHandle = Schedule_scheduleCallback(callback);
  passiveEffectCallback = callback;
}</code></pre>
<p><code>rootWithPendingPassiveEffects</code>&#x662F;&#x5728;<code>commitAllLifeCycles</code>&#x7684;&#x65F6;&#x5019;&#x5982;&#x679C;&#x53D1;&#x73B0;&#x66F4;&#x65B0;&#x4E2D;&#x6709;<code>passive effect</code>&#x7684;&#x8282;&#x70B9;&#x7684;&#x8BDD;&#xFF0C;&#x5C31;&#x7B49;&#x4E8E;<code>FiberRoot</code>&#x3002;</p><pre><code class="lang-js"><span class="hljs-keyword">if</span> (enableHooks &amp;&amp; effectTag &amp; Passive) {
  rootWithPendingPassiveEffects = finishedRoot;
}</code></pre>
<p>&#x8FD9;&#x91CC;&#x5982;&#x679C;&#x6709;&#xFF0C;&#x5219;&#x4F1A;&#x53D1;&#x8D77;&#x4E00;&#x6B21;<code>Schedule_scheduleCallback</code>&#xFF0C;&#x8FD9;&#x4E2A;&#x5C31;&#x662F;&#x6211;&#x4EEC;&#x4E4B;&#x524D;&#x8BB2;&#x7684;&#x5F02;&#x6B65;&#x8C03;&#x5EA6;&#x6A21;&#x5757;<code>Scheduler</code>&#x7684;&#x65B9;&#x6CD5;&#xFF0C;&#x6D41;&#x7A0B;&#x8DDF;<code>PerformWork</code>&#x7C7B;&#x4F3C;&#xFF0C;&#x8FD9;&#x91CC;&#x6211;&#x4EEC;&#x4E0D;&#x518D;&#x91CD;&#x590D;&#x8BB2;&#x89E3;&#x3002;</p><p>&#x4F46;&#x6211;&#x4EEC;&#x770B;&#x5230;&#x8FD9;&#x91CC;&#x5C31;&#x6E05;&#x695A;&#x4E86;&#xFF0C;<code>useEffect</code>&#x7684;<code>destory</code>&#x548C;<code>create</code>&#x90FD;&#x662F;&#x5F02;&#x6B65;&#x8C03;&#x7528;&#x7684;&#xFF0C;&#x6240;&#x4EE5;&#x4ED6;&#x4EEC;&#x4E0D;&#x4F1A;&#x5F71;&#x54CD;&#x672C;&#x6B21;&#x66F4;&#x65B0;&#x7684;&#x63D0;&#x4EA4;&#xFF0C;&#x6240;&#x4EE5;&#x4E0D;&#x4F1A;&#x56E0;&#x4E3A;&#x5728;<code>effect</code>&#x4E2D;&#x4EA7;&#x751F;&#x4E86;&#x65B0;&#x7684;&#x66F4;&#x65B0;&#x800C;&#x5BFC;&#x81F4;&#x963B;&#x585E;DOM&#x6E32;&#x67D3;&#x7684;&#x60C5;&#x51B5;&#x3002;</p><p>&#x90A3;&#x4E48;<code>commitPassiveEffects</code>&#x505A;&#x4E86;&#x5565;&#x5462;&#xFF1F;</p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">commitPassiveHookEffects</span>(<span class="hljs-params">finishedWork: Fiber</span>): <span class="hljs-title">void</span> </span>{
  commitHookEffectList(UnmountPassive, NoHookEffect, finishedWork);
  commitHookEffectList(NoHookEffect, MountPassive, finishedWork);
}</code></pre>
<p>&#x6B63;&#x597D;&#x5BF9;&#x5E94;&#x4E86;<code>useEffect</code>&#x8BBE;&#x7F6E;&#x7684;<code>sideEffect</code>&#x3002;</p></div><div class="api-method-code"><div class="api-method-sample" data-lang="js" data-name="JavaScript"><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">commitHookEffectList</span>(<span class="hljs-params">
  unmountTag: number,
  mountTag: number,
  finishedWork: Fiber,
</span>) </span>{
  <span class="hljs-keyword">if</span> (!enableHooks) {
    <span class="hljs-keyword">return</span>;
  }
  <span class="hljs-keyword">const</span> updateQueue: FunctionComponentUpdateQueue | <span class="hljs-literal">null</span> = (finishedWork.updateQueue: any);
  <span class="hljs-keyword">let</span> lastEffect = updateQueue !== <span class="hljs-literal">null</span> ? updateQueue.lastEffect : <span class="hljs-literal">null</span>;
  <span class="hljs-keyword">if</span> (lastEffect !== <span class="hljs-literal">null</span>) {
    <span class="hljs-keyword">const</span> firstEffect = lastEffect.next;
    <span class="hljs-keyword">let</span> effect = firstEffect;
    <span class="hljs-keyword">do</span> {
      <span class="hljs-keyword">if</span> ((effect.tag &amp; unmountTag) !== NoHookEffect) {
        <span class="hljs-comment">// Unmount</span>
        <span class="hljs-keyword">const</span> destroy = effect.destroy;
        effect.destroy = <span class="hljs-literal">null</span>;
        <span class="hljs-keyword">if</span> (destroy !== <span class="hljs-literal">null</span>) {
          destroy();
        }
      }
      <span class="hljs-keyword">if</span> ((effect.tag &amp; mountTag) !== NoHookEffect) {
        <span class="hljs-comment">// Mount</span>
        <span class="hljs-keyword">const</span> create = effect.create;
        <span class="hljs-keyword">let</span> destroy = create();
        <span class="hljs-keyword">if</span> (<span class="hljs-keyword">typeof</span> destroy !== <span class="hljs-string">&apos;function&apos;</span>) {
          destroy = <span class="hljs-literal">null</span>;
        }
        effect.destroy = destroy;
      }
      effect = effect.next;
    } <span class="hljs-keyword">while</span> (effect !== firstEffect);
  }
}</code></pre>
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